The loss of roundness on wheels on railway vehicles is a known phenomenon, given it increases the stress generated on the track, such as, e.g., the degradation of components of the track, and an increased stress on the railway vehicle, such as, e.g., damage to the suspension elements, affecting the quality of transport, the cost of operation and maintenance. In order to mitigate this effect, rail operators must perform actions in order preserve the roundness values within the range set by railway norms. In the present invention, railway vehicle refers to any type of vehicle capable of running on a railway.
Generally, the loss of roundness of railway vehicle wheels is detected while the vehicle is stationed at a special facility (e.g. a lathe type truing machine, a machining center, or the like). Therefore, there is a need for automatically evaluating and inspecting the roundness of wheels without removing the vehicle from operation, and particularly for planning maintenance servicing. In this regard, it is necessary to inspect the condition of the railway vehicle wheels running on the track, for which prior art has already discussed sensor measuring by means of devices located on the tracks.
WO2010100299 discloses a method for applying strain gauge sensors, electronic devices and signal processing software to achieve a measurement of stress on the track and rail-wheel contact forces on railways and the like. This technique is characterized for comprising a setup using strain sensors arranged in two plates, for each rail, the geometry of which is specifically designed. The plates are bolted to the rail core, settling on it by means of wedges. Although this technique is advantageous for recording the magnitude of stress on the track and wheel-rail contact force, it is not however equivalent to the technical field of the present invention, given this priority does not consider polygonization detection, eccentricity, or loss of roundness of the wheel.
WO2006125237A1 discloses a method for detecting the shape of wheels running on rails, using a section formed by an alignment of measuring elements arranged on the rails, which receives the effects of stress exerted on the rail, and sends electrical signals corresponding to the displacement of the rails in vertical direction, and preferably also in a transverse direction, to an electronic evaluation device to display the shape of the wheels. This prior art device is characterized in that the testing device builds a set of information based on signals, corresponding to at least the circumference of one wheel, and is comprised by a number of information cells. This priority discloses a process characterized in that signals in the testing devices are calculated in terms of the wheel's rotation angle, which is found in accordance with its diameter. Therefore, a drawback of this priority is that it requires the use of at least one additional optical instrument based on laser optics for measuring the corresponding diameter of the wheel.
EP1607726A1 discloses a method and a device that comprises a sensor array, a processing unit, and a computer program for measuring the features of an object running on a railway track. This document comprises sensors adapted for measuring the effects of the force exerted on the rail by an object, the sensors being coupled to a data processing unit forming a measurement area. Furthermore, the data processing unit is adapted for building at least two virtual measurement sub-ranges, so that the first measurement sub-range corresponds to a first part of the measurement area, and the second sub-range corresponds to a second part of the area following the first area. This priority discloses a process comprised of statistical measurements through a significant increase in the measurement area. Therefore, the length of the measurement range should be enough in relation to the wheel's circumference, in order to record sufficient data. With this prior art solution, the measurement area should be larger than the circumference of a typical wheel running on the rail, which induces a problem, namely, that at least one of the adjacent wheels, such as the wheel on the same bogie, moves simultaneously within the measurement area, and thus the measurement of one wheel interferes with the measurement of the other.
DE3309908A1 discloses a method for detecting flattening in railway wheels on circulating vehicles. To this end, the contact force of the wheel on the track is measured continuously for at least one wheel circumference, by measuring the whole circumference or by the measurement of several sections, and using a plurality of measuring points that form a measuring section. This priority is characterized by calculating an average value corresponding to the contact force of a wheel without flattening, and at least one peak value by applying a low-pass filter. The two values are compared with each other, and the difference between these values or their ratio is the measurement for identifying wheel flattening.
Therefore, there is a need for automatically evaluating and inspecting the roundness of wheels without removing the vehicle from operation, and particularly to plan maintenance servicing considering a single point of measurement, and determining the selection criteria through statistical analysis, i.e., to be able to determine a defect in the roundness of railway vehicle wheels with a single measuring point.